AMD Hybrid CrossFire Sneak Peek

AMD / ATI Hybrid CrossFire Technology

Prior to holding its Financial Analyst Day in New York City, AMD showed off some new CrossFire-related technology to a few select members of the press. What we saw was AMD’s Hybrid CrossFire and its associated hardware, which marries next-generation integrated graphics processors (IGP) and entry-level discreet graphics cards for increased performance and functionality. Please note, however, that “Hybrid CrossFire” may not be the official name of this platform when it is made available sometime in early to mid Q108.

If you’re a regular reader of HotHardware, you already know what CrossFire is and how it works, so we won’t go into detail again here. Where Hybrid CrossFire differs from traditional CrossFire is that only a single, discreet graphics card is required for it to work. So, how is it CrossFire with only one graphics card? Let us explain.

AMD’s next generation entry-level graphics cards based on the ATI RV620 GPU architecture, which will be part of the Radeon HD 3400 series when they officially launch, work in conjunction with the GPU integrated into AMD’s upcoming RS780 chipset in CrossFire mode. Just think of the IGP as the second graphics card.

The RS780 series of chipsets will be comprised of multiple SKUs, each with somewhat different feature sets. The IGP in the RS780 is essentially unchanged from the Radeon HD 2400. It will have the same features as a discreet HD 2400 series card, like being able to power dual independent displays and accelerating HD video, and according to current data the RS780’s IGP will offer roughly 3X - 4X the 3D performance of the current 6-series chipsets. We should also note that some RS780 implementations will feature an on-board frame buffer, ranging in size from 16MB to 128MB, dubbed “Sideport”. RS780 boards are expected to be priced in the $70 to $110 range depending on the feature set and particular IGP implementation (some with feature HD video acceleration, others will not). They will also be the first motherboards to feature the upcoming SB700 southbridge.

AMD's Hybrid CrossFire Prototype System

The Radeon HD 3400 series of cards – the Radeon HD 3450 and HD 3470 initially – will have similar configurations to the current 2400 series, but they will be updated with support for DX10.1 and PCI Express 2.0, just like the HD 3800 series. Displayport will also be coming to the some Radeon 3400 series cards in the future, as we’ve already shown. Radeon HD 3400 series cards are expected to be price from about $50 and up.

What this all means is that for around $150 or less, users will be able to purchase a platform that could power four displays, accelerate HD video, and actually play current DX10 games. We saw a system up and running with an RS780 motherboard, a Radeon HD 3450, and a 2.2GHz Phenom 9500 processor, and even with the early state of the drivers and hardware, it was able to play Call of Duty 4 at over 30FPS at 1024x768 with just the IGP, and in Hybrid CrossFire mode performance jumped to over 50FPS. We also saw Unreal Tournament 3 running on the same system. With the IGP alone, UT3 ran at about 27FPS at 1024x768 and scaled to 45FPS in Hybrid CrossFire mode. That’s very strong performance for an IGP, especially considering the games had perfect image quality. Some current IGPs don’t render cutting edge games with very good image quality, if they can run them at all.

Hybrid CrossFire isn’t just about performance though. The platform’s power profile should also be interesting if everything goes according to plan. You see, when the IGP is used to power the display and a 3D application isn’t running, the discreet graphics card can be almost totally shut down, which will reduce power consumption. And the chipset itself is said to consume a maximum of only around 20W.

We should have production level hardware to test Hybrid CrossFire in the coming weeks (if that’s what it ends up being named). When that time comes, we’ll be sure to update you all with full performance and power consumption data. For now, rest assured that tomorrow’s next-gen IGPs are going to be much more interesting than you may think.